I have a non-human race for a (currently) short story series I am writing, and I have been developing him for years. But I do have questions on the biomechanics I have developed and would like to see if what I have designed is feasible.

In the case of this creature, it went from a herding plains based creature (can't remember the exact term) then to escape an ice age his breed went under ground, taking to caves for shelter and eventually becoming a digging species. As such the fore arm and eventual hand, while similar to a humans, have several different changes.

In this races case the fore arm is oriented differently than a humans, ensuring that the palm faces behind the creature, twards the buttoks. In a humans case the palm rests on the thigh naturally. At the base of the wrist (and somewhat a part of it) there is a sort of spur, a bone about one thrid of the length of the forearm that when (through msucle action) is popped down it stablizes and locks the fore arm, preventing any rotation.

The fingers are shorter in relation to a humans, as well as having a greater girth in flesh, bone and muscle tissue. Once the spur is locked down, the hand is forced to lock into a scoop, muscle action holding the hand in place. Doing so allows the creature to apply more strength into the shoveling process of digging.

I also have, from many of the primary joints (knees, elbows, knuckles of hand and toe, back of the jaw) lithoderms with a dense bone base and covered in a very mineral rich kertain (sp?). Would those growths aid int eh digging? Or be more of in the way?

Seems pretty much feasible to me. With a non-human race I recently designed myself, I went as far as developing the organ systems, tissue structures and even cells. It's when you go that deep that you should start getting worried about creating something unfeasible.